to fully simulate it, you could also consider installing it to an alternative directory, such as a chroot environment with --installroot=root. i would create a vm (kvm, virtualbox, vmplayer etc.) with the exact os and do the testing that way, before modifying the actual production OS. others have already suggested that by default yum does not do install until you answer yes, but that is a bit risky i think.
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johnshen64Mar 22 '12 at 17:46